This invention relates to an input/output device for providing multi-axis input to and receiving multi-axis output from an information processing device to control the direction of motion of a referenced object in virtual or real three dimensional (3D) space.
Controllers similar to joysticks are used in various industrial applications to remotely control machinery, for robotics applications and to work pieces during a manufacturing process. In flight simulators, computer games and virtual reality games, a joystick typically provides the 3D interface between the user and the information processing device (or computer) running the flight simulation or game. A controller or joystick operates by generating electrical signals proportional to the displacement of a control level in the direction of each axis. U.S. Pat. No. 4,281,561 to Groskopfs, "Three Axes Controller," U.S. Pat. No. 5,589,828 to Armstrong, "6 Degrees of Freedom Controller Capable of Tactile Leedback," and U.S. Pat. No. 4,795,952 to Brandstetter, "Joystick For Three Axis Control of A Powered Element" describe typical joystick type controllers.
Joysticks and industrial controllers provide generally only a rough representation of an object in three dimensional space. Additionally, because of the length of the control lever, such controllers lack sensitivity to smaller increments of movement and do not provide a comfortable feel or feeling for the environment (real or virtual). Such prior art controllers, while useful, generally provide poor control of the relative real or virtual 3D environment. This disadvantage renders inaccurate approximations for the user's virtual or real 3D space and is uncomfortable or exhausting to the user.
U.S. Pat. No. 5,491,497 to Suzuki, "Multi-Way Input Device," describes a device for three-dimensional input to an information processing device in which the user inputs directional inputs through movement of a spherically shaped operating member which lies outside a spherically shaped housing. Movement of the operating member relative to the housing activates switches on a substrate within the housing which detect rotation in the X, Y, and Z axes. A defined movement in the sensed direction becomes, for example, a cursor movement on a television screen in two axis directions, namely in the right and left directions and the direction perpendicular to the surface. A separate actuator is also provided which enables the user to move a cursor in a uniaxial direction. Each sensed direction is achieved by a single switch arrangement and typically depression of such switches is nominal. Such limited motion, though quick in operation, is a significant drawback from human interaction relating to an object referenced in three-dimensional virtual or real space. Furthermore, Suzuki's multi-way input device is limited to use on a planar surface; motion is confined only to a downward direction because no resistance to upward motion is provided. If the device is not anchored in any fashion, uniaxial motion in the Z-axis is eliminated.
Traditionally, joysticks and controllers require only one hand to manipulate referenced objects in 3D space. Suzuki's spherically shaped controller requires two hands to operate, but it is not ergonomic; the controller is not held by the user, rather the user places one hand on the housing and the other hand on the operating member and moves one relative to the other. Also, translational motion is counter-intuitive. In Suzuki, the user must first move the operating member relative to the housing to select a direction of movement, then h e must activate a switch to start the cursor moving in that direction. Furthermore, Suzuki's device has no capability for tactile feedback response from the 3D virtual or real space; feedback is passive and limited to the depression length of the switches.